thank you both for being with us. >> woodruff: you can watch all of mitt romney's speech at v.m.i. today on our web site. >> brown: still to come on the newshour, a deadly meningitis outbreak; the stem cell breakthrough; rothenburg, page, and kohut on the campaign; and salman rushdie on life under a death sentence. but first, the other news of the day. here's hari sreenivasan. >> sreenivasan: the investigation into the killing of the u.s. ambassador to libya took new turns today. cbs and abc news reported american officials in libya had asked for more security personnel, but the state department refused. meanwhile, libyan officials said president obama's top counterterror advisor, john brennan, will be in libya tomorrow to discuss the investigation. a warning from congress today: u.s. companies should stop doing business with china's top two telecommunications firms, huawei technologies and z.t.e. the house intelligence committee reported both have close ties to the government of china. it said using their components in u.s. computer networks could let them steal trade secrets or e